1hgf

How Influenza Escapes Vaccines
Influenza hemagglutinin, the structure of which is shown here, is a glycoprotein on the surface of influenza virus particles that enables them to attach to and infect host cells. Antibodies that bind to hemagglutinin are a major defense mechanism that prevent infection. The RNA genome of influenza is characterized by a high mutation rate. Mutations on the surface of hemagglutinin tend to be protective for the virus. They tend to be retained because they tend to reduce the binding strength, and hence the host defensive capability, of antibodies that recognize the un-mutated hemagglutinin. Influenza vaccines include hemagglutinins and they induce anti-hemagglutinin antibodies in vaccinated individuals. Often, however, by the time the vaccines can be designed, produced, and disseminated, mutant influenza viruses have arisen that can cause disease in vaccinated individuals.

If you show the Evolutionary Conservation of the structure on this page (using the blue bars below the molecule), you will see highly variable surface amino acids. These represent sites of mutations that have been retained in wild strains of influenza because they improve virus survival.

About this Structure
1HGF is a 6 chains structure of sequences from Unidentified influenza virus. Full crystallographic information is available from OCA.

Notes and Literature Cited
Page seeded by OCA on Wed Feb 18 07:40:45 2009